A programmable gain amplifier (PGA) is employed in many signal processing applications where adjustable signal gain is required. Example applications include audio signal processing, video signal processing, image processing, and control systems, to name a few. In one example, an adjustable volume level can be provided in an audio system by gain scaling signals in the pre-amplifier with a PGA. In another example, an image sensor is arranged to work with a PGA such that the PGA provides gain scaling of the signals from the sensor such as in a CDS (Correlated Double Sampling) circuit arrangement.
The described analog signal processing applications may utilize a PGA that is capable of amplifying a wide range of analog input signals. The PGA may also require fine control over the gain that is applied to the analog input signal. As target resolutions and operating speeds increase various non-ideal effects in the circuits may result in undesirable performance. The present disclosure contemplates a variety of non-ideal effects in switched capacitor PGA circuits.